The present invention relates generally to power converters, and in particular to a system and method for synchronizing parallel power converters.
Power converters are used to convert an input power from a power source into an output power suitable for a load. For example, a load may require three-phase alternating current (AC) power to operate, but the power bus may provide direct current (DC) power. In order to power the load, a power converter must be implemented to convert the DC power from the power bus into the three-phase AC power for the load.
In some systems, it is desirable to provide power to a load from multiple converters. When two or more power converters are connected in parallel, additional current paths are created. This can result in current recirculation, which is undesirable in that it increases current components at various frequencies (e.g., ripple) within the converters and decreases conversion efficiency. To accommodate higher current peaks, components may be oversized during design of the converter. Large recirculating currents could also decrease performance, increase stress on the devices which may reduce the lifetime of the converter, and in some cases even damage components of the converter. It is desirable to efficiently eliminate recirculation current without the need for additional, costly, components or oversized devices.